Modification of https://www.youmagine.com/designs/carriage-roller-for-kossel-w-openbuilds-2020-v-slot-extrusion-mini... to allow use of Openbuild's Solid V Wheels (24mm OD) - . http://openbuildspartstore.com/openbuilds-solid-v-wheel-kit/. The spacers are to replace the 6mm spacers included with the kit - for my kossel, they were approx 1.7mm too long. If you are using these wheels and they don't sit perfect, you may have to adjust the height in the spacers.scad file until they fit and don't wobble.